Pumps



INVENTOR. KENNETH R. LUNG ATTORNEYS K. R. LUNG May 12, 1959 PUMPS FiledMarch 18, 1957 FIG-T United States Patent PUMPS Kenneth R. Lung, Dayton,Ohio, assignor to The Tait Manufacturing Company, Dayton, Ohio, atcorporatom of Ohio Application March 18, 1957, Serial No. 646,693Claims. (Cl. 103-87) This invention relates to submersible pumps.

The invention has particular relation to submersible pumps of the typeincluding a motor as a part of the entire assembly which is submerged ina well, and with the motor depending below the pump. If such motor is ofthe totally enclosed type, it is necessary to provide a rotary seal atthe junction of the motor shaft and the top of the motor casing wherethe shaft extends upwardly to the pump portion of the assembly. Pumps ofthis type are commonly subject to use with relatively sandy water,particularly during the initial period of use of a well, and such sandin the water constitutes a danger to the seal between the shaft andmotor casing, since if the seal should be abraded sufiiciently to leak,the motor may be flooded and spoiled.

It is a primary object of the present invention to provide a rotary sealfor a submersible pump which is so constructed and arranged as tominimize the possibility of damage by sand in the water handled by thepump even after extended periods of use.

An additional object of the invention is to provide such a rotary sealwhich is so constructed that the natural forces incident to operationthereof in use in a submersible pump assembly tend to dispel sand fromaccess to the relatively moving sealing parts.

It is also an object of the invention to provide a rotary sealconstruction having the advantages outlined above which in addition canbe removed and replaced with maximum ease whenever such operation isnecessary or desirable.

Further objects and advantages of the invention will be apparent fromthe following description, the accompanying drawing and the appendedclaims.

In the drawing- Fig. 1 is a perspective view illustrating a submersiblepump assembly of the type to which the present invention relates;

Fig. 2 is an enlarged fragmentary view in axial section through theconnection between the pump and motor portions of the assembly of Fig.1, the view being a section on the line 22 of Fig. 3;

Fig. 3 is a radial section on the line 33 and Fig. 4 is a fragmentarysection on the line 44 of Fig. 2.

Referring to the drawing, which illustrates a preferred embodiment ofthe invention, the submersible pump assembly shown in Fig. 1 includes amotor casing 10, a pump shell 11, and an intake cap 12 which connectsthe parts and 11 and is covered by a screen 13. The motor shaft 15extends upwardly from the casing 10 into the interior of the cap 12 andis there connected by a coupling 16 to the pump shaft 17. Fig. 2 alsoshows a fragment of the impeller 18 and cover 19 of the lowermostpumping stage in casing 11, these parts being indicated as of thestructure shown in my copending application Serial No. 633,412, filedJanuary 10, 1957, and assigned to the same assignee as this application.

of Fig. 2;

The construction of the intake cap 12 and its connection to the motorcasing 10 are best seen in Figs. 2 and 3. A bracket 20 forms the upperend of the motor assembly, and it is secured in sealed relation with theupper end of casing 10 as by means of screws 21 and O-ring 22. Anannular shoulder 25 projects upwardly on the upper surface of bracket 22in concentric relation with shaft 15, this relationship beingestablished by the bearing portion 26 of bracket 20 in which shaft 15 isjournaled by a bushing 27.

The shoulder 25 serves also to locate the intake cap 12 in concentricrelation with the motor casing and the motor shaft 15. The base portionof cap 12 is formed as a relatively flat internal flange 30 which seatson the upper surface of bracket 20 and is provided with a concentricthroughbore 31 proportioned for close fitting telescoping engagementwith the shoulder 25. Bosses 32 on the upper surface of flange 30receive screws 33 which secure the cap 12 to bracket 20, and the cutawayopening 34 in flange 30 is to receive the motor cable 35, which isprovided with a sealing gland 36 where it passes through bracket 20 intothe interior of motor casing 10. The flange 30 is connected with theupper portion of cap 12 by ribs 37 which are spaced angularly from eachother to provide the inlet passages to the inlet chamber within cap 12.

The rotary seal assembly provided by the invention is indicatedgenerally at 40 and is located within the intake cap 12. Referringparticularly to Fig. 4, the seal includes a rotary sealing ring 41 whichmay be of carbon or other suitable material and is secured in sealedrelation on shaft 15 as by means of a rubber sleeve 42 and clamping ring43. The rotary sealing ring 41 engages a complementary stationarysealing ring 44 which is secured as by means of a rubber sleeve 45 in acounterbore 46 within the shoulder 25. The rings 41 and 44 are shown asmaintained in sealing arrangement in the usual way, by means of spring47, a metal sleeve 48, and back-up plate 49 held axially on shaft 15 bymeans of a snap ring 50 in a groove 51.

In accordance with the invention, the several parts of the seal as justdescribed are so proportioned and arranged that the upper surface ofstationary sealing ring 44 is located above the plane of the surroundingarea of the shoulder 25 and flange 30. With this construction, any sandentering the interior of inlet cap 30 cannot efl'ectively reach thecomplementary sealing surfaces of the rings 41 and 45. Thus not only isthe surface 55 higher then the surrounding surfaces so that sand doesnot tend to stay thereon even when the parts are at rest, but when thepump is in operation, the rotation of ring 41 and its associate parts ofthe seal will tend to produce outward currents which would sweep anysand off the surface 55.

If the rotary seal assembly were incorporated within the bracket 20, orotherwise located internally of motor casing 10, and if then sand shouldenter and reach the sealing ring 44, damage to the seal or to otherparts within the casing would be most likely to occur, and this isparticularly true in view of the difiiculty of eliminating such sandonce it had entered. With the present invention, however, the naturalforces present in the operation of the rotary seal cooperate to minimizethe possibility even of access by sand to the sealing parts, and thuseven further reduce the possibility of entry of sand between the sealingsurfaces of the rotary and stationary ring. The possibility of abrasionof these parts is therefore most remote, but if they should needreplacement, as because of natural wear, they are accessible for easyservicing upon simple removal of the screen 13 and coupling 16.

As an illustration of proportions of these parts which have been foundsatisfactory, with a motor casing having an overall diameter of theorder of 4 inches, the shoulder 25 and flange 36 may each be inchmeasured axially of shaft 15, and the ring 44 may be formed of a ceramicmaterial and may also be inch thick. With these dimensions, the rubbermounting sleeve 45 of the relative proportions shown in Fig. 4 issufiicient to support the ring 44- with its upper surface 55 above thelevel of the end of shoulder 24. Furthermore, even if ring 44 werebottomed in counterbore 46, its surface 55 would still be not less thanflush with shoulder 25, and this would provide equivalent advantages solong as the surface 55" is not lower than the surrounding areas to establish a recess where sand might collect.

While the form of apparatus herein described constitutes a preferredembodiment of the invention, it is to be understood that the inventionis not limited to this precise form of apparatus, and that changes maybe made therein without departing from the scope of the in vention whichis defined in the appended claims.

What is claimed is:

1. In a submersible motor including a motor shell sealed at the lowerend thereof and having a drive shaft projecting from the upper endthereof, the combination of a bracket secured in sealed relation withsaid upper end of said sheil and receiving said shaft therethrough, saidbracket being exposed at the top thereof for direct access by liquidwherein said motor is submerged, a rotary sealing ring surrounding saidshaft above said bracket, flexible means securing said ring in sealedrelation with said shaft providing for limited movement of said ring onsaid shaft, means on said shaft biasing said ring toward said bracket, astationary sealing ring located below said rotary sealing ring forsealing engagement between the upper surface thereof and said rotaryring under the biasing action of said biasing means, means securing saidstationary ring on the upper end of said bracket, and said securingmeans being proportioned to support the upper surface of said stationaryring above the surrounding area of said bracket to prevent accumulationof sand therein.

2. In a submersible motor including a motor shell sealed at the lowerend thereof and having a drive shaft projecting from the upper endthereof, the combination of a bracket secured in sealed relation withsaid upper end of said shell and receiving said shaft therethrough, saidbracket being exposed at the top thereof for direct access by liquidwherein said motor is submerged, said bracket having a counterbore inthe outer end thereof surrounding said shaft, a stationary sealing'ringsecured within'said counterbore, a rotary sealing ring surround-- ingsaid shaft above said stationary ring, flexible means securing saidrotary ring in sealed relation with said shaft providing for limitedmovement of said rotary ring on said shaft, means on said shaft biasingsaid rotary ring into sealing engagement with the upper surface of saidstationary ring, and said stationary ring being proportioned to extendaxially above the surrounding area of said bracket to preventaccumulation of sand on said upper surface thereof.

3. In a submersible motor including a motor shell sealed at the lowerend thereof and having 'a drive shaft projecting from the upper endthereof, the combination of a bracket'secured in sealed relation withsaid upper end of said shell and receiving said shaft therethrough, saidbracket being exposed at the top thereof for direct access by liquidwherein said motor is submerged, an annular shoulder projecting upwardlyon said bracket above the surrounding area of said bracket in concentricrelation with said shaft, a rotary sealing ring secured to said shaftabove said shoulder, a stationary sealing ring secured within saidshoulder, means biasing said rotary sealing ring into maintained sealingengagement with said stationary ring, and said sealing ring beingproportioned to locate said upper surface thereof axially above saidshoulder to prevent accumulation of sand thereon.

4. In a submersible pump assembly including a submersible motor casinghaving a drive shaft projecting above the upper end thereof and a pumphaving a driving connection with said shaft, the combination of anintake cap connecting said pump and said motor casing and defining aninlet chamber extending therebetween through which the liquid whereinsaid assembly is submerged fiows to said pump, a rotary sealing ringsecured on said shaft for rotation therewith within said inlet chamberin facing relation with said motor casing, a stationary sealing ring forengagement by said rotary ring, means mounting said stationary ring onthe upper end of said motor casing within said inlet chamber, meansbiasing said rotary sealing ring into maintained sealing engagement withthe upper surface of said stationary ring, and said stationary ring andsaid mounting means therefor being proportioned to maintain said uppersurface of said stationary ring above the surrounding area of saidcasing end to prevent accumulation of sand on said ring surface.

5. In a submersible pump assembly including a submersible motor casinghaving a drive shaft projecting above the upper end thereof and a pumphaving a driving connection with said shaft, the combination of anintake cap connecting said pump and said motor casing and defining aninlet chamber extending therebetween through which the liquid whereinsaid assembly is submerged fiows to said pump, a bracket forming theupper end of said casing, a flange on the lower end of said intake capseated on said bracket and having a central throughbore, an annularshoulder extending upwardly on said bracket in concentric relation withsaid shaft and projecting through said bore in said flange to locatesaid cap and said casing in coaxial relation, a rotary sealing ringsecured on said shaft within said inlet chamber and above said shoulder,a stationary sealing ring for engagement by said rotary ring, meanssecuring said stationary ring within said shoulder and with the uppersurface thereof extending above the surrounding area of said shoulderand said flange to prevent accumulation of sand on said surface thereof,and means biasing said rotary ring into maintained sealing engagementwith said upper surface of said stationary ring.

References Cited in the file of this patent UNITED STATES PATENTS2,268,218 Lurn Dec. 30, 1941 2,577,559 Armstrong et al. Dec. 4, 1951.2,668,068 Bredemeier Feb. 2, 1954 2,682,229 Luenberger June 29, 19542,722,892 French Nov. 8, 1955 2,766,696 Lung Oct. 11, 1956 2,786,952Pleuger Mar. 26, 1957 FOREIGN PATENTS 434,505 Great Britain Sept. 3,1935

